The photographic performance (e.g., sensitivity and gradation and, in particular, fog) of a photographic silver halide light-sensitive material (hereinafter sometimes referred to merely as a "light-sensitive material") is liable to vary during the storage or when the light-sensitive material is stored for long periods of time. This variation in photographic performance with a lapse of time cannot be completely removed, but is desirable to be minimized. For this purpose, a number of investigations have heretofore been made.
It is known that to prevent the variation of photographic performance occurring during the storage of the light-sensitive material or the development thereof, heterocyclic compounds such as 1-phenyl-5-mercaptotetrazoles (as described in, e.g., Belgian Pat. No. 671,402, U.S. Pat. Nos. 3,295,976, 3,376,310, 3,615,616, 3,071,465, 3,420,664, 2,403,927, and Japanese Patent Application (OPI) No. 37436/75 (the term "OPI" as used herein refers to a "published unexamined Japanese patent application")), benzotriazoles (as described in, e.g., British Pat. Nos. 919,061, 768,438, U.S. Pat. Nos. 3,157,509, 3,082,088, and German Pat. No. 617,712), benzimidazoles (as described in, e.g., U.S. Pat. Nos. 3,317,578, 3,148,066, 3,511,663, British Pat. Nos. 271,475, 1,344,548, and German Pat. Nos. 708,424, 635,769, 2,205,539), and indazoles (as described in, e.g., U.S. Pat. Nos. 3,106,467, 3,420,670, 1,763,990 and 2,271,229) are added to light-sensitive materials or processing solutions. These compounds, however, have disadvantages in that their ability to inhibit the increase of fog during the storage is poor and they cause a reduction in sensitivity.
In color photographic light-sensitive materials, particularly those color photographic light-sensitive materials for cameras, the amount of silver salts as used therein is large and, furthermore, colloidal silver is used in a yellow filter layer and an antihalation layer. For this reason, the time required for the bleaching process is lengthened, and this constitutes a serious obstacle to the increase of the processing speed. 1-(Amidophenyl)-5-mercaptotetrazole, for example, is known as a compound having a high fog-inhibiting ability among the known antifoggants. This compound, however, suffers from the disadvantage that the processing speed is further decreased, since it readily forms a stable salt with silver and retards desilvering at the bleaching stage. This tendency is noticeable particularly when bleaching agents having a low bleaching force, such as persulfates, are used.
Hence, it is desired to obtain stabilizers which are capable of preventing the variation in photographic performance during the storage without retarding desilvering. However, none of the known compounds meets the foregoing requirement.